It is well known that various systems in a vehicle may be cooled via a fluid (e.g., coolant) system or loop. For example, heating, ventilation, and air conditioning (HVAC) systems in vehicles include a fluid system or loop that exchanges heat to allow the vehicle cabin to be heated or cooled. This HVAC fluid system may contain a plurality of heat exchangers isolated within the HVAC fluid system itself. It is known that the HVAC fluid system and the hybrid powertrain coolant system may be in thermal communication with one another to exchange heat between the two systems.
Such HVAC fluid systems may have three binary state (on/off) refrigerant shut-off valves, one for each heat exchanger, and each valve being upstream of the associated heat exchanger. All three heat exchangers may be supplied with refrigerant from a respective fluid line that branches from a single source such as an AC condenser.